Fix compiler warning.
Fix compiler warning.

CompendiumSoftware/beanstalkd,wyzssw/beanstalkd,Qihoo360/beanstalkd-win,naderman/beanstalkd,qbdsoft/beanstalkd,aidaima/beanstalkd,aidaima/beanstalkd,mobliyishengyuan/beanstalkd,r3jack/beanstalkd,cgvarela/beanstalkd,wfxiang08/beanstalkd,tdg5/beanstalkd,pinguo-xudianyang/beanstalkd,yetone/beanstalkd,handautsav/beanstalkd,mickeyouyou/beanstalkd,r3jack/beanstalkd,diditaxi/beanstalkd,CompendiumSoftware/beanstalkd,potatosalad/beanstalkd,wyzssw/beanstalkd,orangeholic/beanstalkd,cgvarela/beanstalkd,lzpfmh/beanstalkd,yetone/beanstalkd,justintung/beanstalkd,amyvmiwei/beanstalkd,PhillipMwaniki/beanstalkd,diditaxi/beanstalkd,qbdsoft/beanstalkd,mickeyouyou/beanstalkd,tdg5/beanstalkd,bmhatfield/beanstalkd,naderman/beanstalkd,kr/beanstalkd,bmhatfield/beanstalkd,naderman/beanstalkd,JensRantil/beanstalkd,kr/beanstalkd,davies/beanstalkd,wfxiang08/beanstalkd,LomoX-Offical/beanstalkd-win,Qihoo360/beanstalkd-win,orangeholic/beanstalkd,JensRantil/beanstalkd,justintung/beanstalkd,lzpfmh/beanstalkd,amyvmiwei/beanstalkd,mobliyishengyuan/beanstalkd,potatosalad/beanstalkd,LomoX-Offical/beanstalkd-win,handautsav/beanstalkd,ifduyue/beanstalkd,PhillipMwaniki/beanstalkd,davies/beanstalkd,pinguo-xudianyang/beanstalkd,ifduyue/beanstalkd